blatt



March l2, 19,63

L. F. BLATT WORK EXTRACTOR ARM FOR A PRESS Filed May 8, 1961 4 Sheets-Sheet 2 INVENTOR.

EZAND E BLDTT.` Y

ATTORNEY' March 12, -1963 L. F. BLATT 3,080,983

WORK EXTRACTOR ARM FOR A PRESS Filed May 8, 1961 4 Sheets-Sheet 3 INVENTOR.

iM/V0 E L47'7 y 50 Il -ll 49 Kaff/Mm 4 Arme/vir March 12, 1963 L; F. BLATT 3,080,983

WORK ExTRAcToR ARM FOR A PREss Filed May l8. 1961 4 Sheets-Sheet 4 -55 i Arran/:y j

United States Patent This invention relates to a workpiece extractor arm `for presses, and more particularly to an extractor arm for removing sheetrnetal stampings or orgmgs from their ldies.

Alt is the object of the present invention to provide a workpiece extractor arm which not only eliminates a personal and safety hazard, but also increases productive efiiciency. The primary object ofthe vpresent invention is the provision of an overhead swinging device applicable -to large presses, the arm to be swung from a single stationary pivot point giving the arm great rigidity, while the lower extremity thereof where the pickup jaw attaches would instead of inscribing a true arc when moving through 'la 90-degree swing, would start with a definite rise, inscribed i jthereafter as nearly as `possible an angular straight line relative to the horizontal and then enter an arc.

I-t is a further obiect of the present invention to provide an extractor arm, which at approximately two-thirds `of its swinging movement, incorporates a telescopic telescoping arm section which reverses in direction to thus produce a reverse inertia condi-tion on the part being vgripped by the jaw for a 180 degree part turnover without the use of any auxiliary turning devices.

These and other objectswill be seen from the following specification and claims in coniunction with the appended drawings in which:

FIG. 1 is a side elevational View of the present workpiece extractor arm in inoperative position and as attached to a press, fragmentarily shown.

FIG. 2 is a right side elevational View thereof.

RG. 3 is a fragmentary view similar to FlG. v1, but on an increased scale lfor better illustration of details.

FIG. 4 is a section ltaken on line ft-fiof FlG. 3.

FlG. 5 is a fragmentary section taken on line S--S of FIG. '4, illustrating the safety locking mechanism.

FIG. 6 is a fragmentary section taken on line 6--6 of FIG. 3.

FIG. 7 is a fragmentary section taken on line 7 7 oi FIG. 3.

`lt is understood ythat the above drawings illustrate merely a preferred embodiment of the invention, and that other embodiments are contemplated within the scope of `the claims hereafter set forth.

VReferring to FlGS. l and 2, the present (line Arc) extractor arm is shown .in anormal waiting position, and includes the body 11 defined by `a pair of spaced upright side plates 12 and an angular cylinder' support plate 13 interposed therebetween and iixedly secured thereto by aseries of fasteners 14, there being additional spacers 15 interposed between the plates 12 and secured thereto by cap screws 16, FIG. l.

VAn undercut notch 17 is machined through upper portions oi the plates 12 so `as to be supportably hung or 'mounted upon cross bar 1S, which forms a part of the adjustable press mount, generally indicated at 19, FIG. 2,

being shownin dotted lines, adapted for securing to the press by the 'fasteners Ztl.

An additional V.spacer 21 is interposed between the plates Y12 and carries a transverse set screw 22, FIG. 2, `for frictional engagement with the cross ybar 18, for the "purpose of holding body side plate-'assembly firmly against the upper hanger cross bar.

The hanger assembly also includes a lower cross bar 122, which is transversely threaded'to :receive the boltdown-screws 24, which extend through-the angle clips `23.

.42 and through 3,080,983 Patented Mar. 12, 1953 Swing Plate Assembly The swing plate assembly, generally indicated at 36,

"FG. 4, includes a pair of upright parallel spaced plates 31, including tubular' spacer 32 at its upper end, through which extends the bearing'shaft 33 pinned thereto at 34 with respective ends of the said shaft 33 supportably iournaled within the roller bearing assemblies 37 secured through the body plates 12 and respectively covered by the caps 33.

The centrallocation of the swing plate assembly Sil is maintained between the side plates 12 by the preferably bronze wear washersuSS which bear against the bosses 36 upon the interior surfaces of plates 12. The covers 3S rfor the bearings are retained upon plates 12 by' the cap Vscrews 39 shown in FIG. l.

The swingvplate assembly, including the parallel spaced plates 3l, also includes between the said plates the spacers 4u and 41, FlGS. l and 4, as well as the brake cylinder .spacer 42, best shown in FIG. 6, being remote from the main pivotal mounting 33 of the swing 'Ti-LQ plate assembly 30. said brake cylinder spacer includes a pair of bronze friction plungers 4.3, which slidably extend into the spacer the respective plates 31 for frictional engagement with the interior surface portion of the body plates 12, there being a suitablecoiled spring d4 interposed in compressi-on between `the inner ends :of the plungers a3, normally urging the same outwardly.

As .an alternative construction, Vthe plunger may include {lt-ring seals d5 intermediate their ends, and at their outer ends the brake linings 46 for frictional engagement with the vinterior surfaces of the plates 12. ln this case, a plug d5v from the spacer sleeve 42 is removed and the conduit d'7 connected therewith which receives iluid under pressure from the threeway valve 48 connected with source `et' pressure P, which may be compressed air preferably, or hydraulic iiuid. l

Even with the use of pressure iluid operating upon the in .er ends of lthe plungers 43, the spring ed under cornpression still maintains some friction of the outer ends of said plungers with respect to the inner surfaces of the plates 12, forming a part of the body 11.

By employing the auxiliary air pressure, braking pre"- sure may now be applied at any/'desired point inthe movement of the swing plate assembly 3l), as desired, with the braking pressure being controlled by the diameter of the ends of the plunger' together with the applied air pressure, for illustration. Thus provision is made for pivotally mounting the swinar plate assembly Eil with respect to stationary body 11 and with means for effectively spacing swing plate assembly relative to -said body.

Support Assembly angular adjustment, said fastening means also including a series of opposed dowel pins 51, FIG. '4. y

vBetween the pair of spaced -plates 4,9, there iis -secured 3 i an elongated sleeve 52 with counterbores at its opposite ends to receive the longitudinally spaced bushings 53 retained therein by the snap rings 54, FiG. 4.

Telescopz'ng Arm Assembly A telescoping arm assembly, including the tubular arm 55, is slidably positioned through the said bearings 53 and extends downwardly from the support assembly 49, FIG. 1 and carries at its lower end the split clamp collar 56 employing a pair of cap screws 57 for adjustably securing the mount arm 58, which is slidably provisioned within the telescoping arm 55, and fixedly secured thereto.

Bracket 59 at the lower end of the mount arm 58 receives and has secured thereto the lower end of the adjusting screw 6i), whose upper free end portion extends through the auxiliary bracket 62 on clamp 56 and is adjustably secured thereto by the nuts 63', FIG. 1. This provides a means of effecting a longitudinal adjustment of the mount arm 58 with respect to the telescoping arm 55, after which the assembly is xedly Secured together.

The bracket assembly 59 includes, or has connected thereto, split holding clamp assembly 63, which supports the transversely arranged power roller automation jaw assembly, generally indicated at 64.

Jaw Assembly The jaw assembly includes the hanger rod 65, which is horizontally disposed and adjustably secured within the clamp 63. The opposite end of the hanger rod carries the mount 66 supporting the pneumatic cylinder 67, which has a reciprocal piston and attached piston rod 68. The mount 66 has slidably provisioned therethrough the elongated guide rod 71, with stop 72 at one end, and which at its opposite end carries the jaw head 69 with the fixed 'aw 70. J Arranged below the fixed jaw 70 is the angularly movable jaw 73, which through a suitable linkage, is connected with the piston rod 68 for controlling opening and closing of the jaw 73 relative to the jaw 70 for gripping the work in the press to be removed therefrom.

The structure of the present jaw is more fully set forth in my pending patent application, Serial No. 803,424, tiled April 1, 1959, entitled'Power Operated Jaw Assembly, now Patent #3,013,835 dated December 19, 1961 and further details as to the operation thereof are omitted. Suflice to say, however, that in the position of the jaw part as shown in FIG. l, initial activation of the cylinder 67 by application of air pressure to the left hand port 124 causes the piston rod 68 to move to the right, effecting longitudinal-movement to the right of the jaw head 69 until the stop 72 engages the body 66, thereafter further longitudinal movement of the piston rod 68 causes the jaw 73 to close relative to the jaw 70, after which the present extractor arm is activated for withdrawing a workpiece from a press, as hereinafter described in further detail.

The telescoping arm 55, through the arm mount 58, clamp assemblies 59-63 movably mount and support the power operated jaw for the purpose of withdrawing a workpiece from a press along the path of movement, generally indicated at 97, FIG. 1, hereafter described.

The said telescoping arm S is retained and guidably positioned by the link 75, shown in FIG. 4, which is pivotally connected as at 76 to the clevis 74, which is xedly secured within the inner end of telescoping arm 55, within the swing plate assembly 30. Link 75 at its other end guidably positioned within the axial slot 77 of the clevis 78, is ixedly secured to reciprocal piston rod 79 connected with the air cylinder 81 hereafter described, particularly shown in FIG. 2, as well as FIG. 1.

The link 75 is pivotally retained with respect to clevis 78 by the follower shaft 80, which extends transversely therethrough. The air `cylinder 81 includes a series of 4tie rods 82, FIG. 1, by which the said cylinder is secured to the cylinder mounting plate 13 for effecting controlled vjournaled and retained upon the follower shaft by washers 87 and fastening nut 88 and are adapted for movable positioning within the elongated slots 87 formed in the body plates 12, which slots 87 are angularly related with respect to the swing plate slots for the purpose hereafter described in effecting pivotal movements of the swing plate assembly.

The piston rod 79 and the relative attached parts thereon, is fully extended in a normal position shown in FIG. l. The inside set of roller followers 84 nest on and at the bottom of the swing plate slots 85. The outer set of roller followers 36 are arranged within the body plate slots 87 so as to provide a clearance 90 in the fully extended normal position.

To assure adjustable rigidity of the arm -assembly 55 in the normal pickup position, a set of take up blocks 91 are adjustably fastened within elongated slots 92 in the body plates 12 and adjustably secured thereto by the fasteners 93, which extend through elongated slots in the said blocks 91.

Set screw 95 is adapted for operatively and adjustably engaging the take up blocks 91, of which there is one on each of the outer surfaces of the respective body plates 12, for registry with the corresponding follower roller 86 when it is positioned adjacent the lower end of the slot 87, and thus are adapted to take up and compensate for any future wear of the slot 87, as at point 96, shown in FIG. 7.

Operation In view of the angular relation between the respective slots 85 and 87, if the piston rod 79 of cylinder 81 is caused to retract, carrying therewith the clevis 78 and follower roller assembly 80-84--86, the said rollers 84 and 86 will respectively react against the sides of the plates 31 and 12 within the respective above described slots. Body 11, being a stationary member, with angular slots 87, a swinging action is -transmitted to the swing assembly 30 by its followers rollers 84.

At the same time, the telescoping arm 55 and the parts connected thereto, through the action of the clevis 74, are drawn upwardly, as shown in FIG. 1, or in effect become shortened relative to support plate assembly 49. Therefore, as the swing plate assembly 30 swings through an arc indicated by the dotted line 97, FIG. 1, the telescoping arm 55 becomes shorter, relative to the main pivot point 33 of the swing plate assembly 30.

Accordingly, any mechanism secured at the end of the telescoping arm 55, such as the jaw assembly 64 and connected workpiece from a press, for example, instead of inscribing a circular arc 128 from the main pivot 33, inscribes a new path 97, as controlled by the angular relationship of the slots 87 and 85 and the withdrawing movement of the arm assembly 55.

At the start of the follower roller movement, a lift 98 is applied to the arm 55, after which there is defined a straight line movement at an angle relative to horizontal as shown at 99 which in -turn merges into an arc 100. During this movement, arm 55 reversed direction 90 as slot 85 shifts 90 so that a workpiece gripped by jaw 64 fastened to arm 55 turns over 180.

Safety Lock Mechanism When the swing plate assembly 30 reaches the top of its swing,` as shown in dotted lines inFIGS. 1 and 3, limited -by the outside set offollowerrollers 86 reaching the ends of the slots 87 in the -body plates 12, the 180 degree circular cutouts 101, shown in FIG. 3 on plates '31,r have passed through the milled slots 102, formed through one-half the diameter of the lookup pin 103, shown inFlG. 4, and alsoshown in FIG. 5.f

The center line of the pin 103 is placed in such a manner relative to the center line of cutouts 101 as to allow for a swinging clearance. yWhen the lock pin 103 is rotated 180 degrees, controlled by the lock collar 104 and the handle 106, the half of the diameter of the lockup pin 103 which is not machined, now fills the cutout-s 101, as at S, FIG. 5. Accordingly, if the holding force upon the Swing plate ass'em-blywe-re released, the swing plates 31 would be retained in the locked up position until released by again applying actuating force and rotatfingrthe loc-l: pin 103 to the open or operating position.

As best shown in FIG. v4, the lock pin 103, with the 180 degree slots 102 therein, Aextends between therbody plates 12 and is pivotally journaled therebetween relative to the lock collar104. The set screw 107, associated spring 108, and ball 109, provide for la detent assembly, FIG. 4, for maintaining the lock vpin 103 in the desired Aposition of rotated adjustment, i.e., open or closed with the ball 109 registering with one of the pair of radially related apertures formed in the lock pin 103.

Interlock Switch Mount Assembly fIlle interlock 4switch `mount assembly is generally indicated at 11), FIG. 3, and provides a means for adjustvably mounting `the limit switch 116. For Ithis purpose there is provided an elongated tubular body 111 anchored to one of the -body plates 12, as by fasteners 112. Elongated screw 113 is journaled through the tubular housing 111 and retained against relative longitudinal movement therein and is rotated by means of a suitable handle 114 at one end.

Elongated nut 115 is threaded upon lthe screw 113 within the housing 111, extends through an elongated slot in the upper surface of the cylindrical housing 111 for securing to the limit switch 116. It is noted that the follower shaft 80 has extended end portions at 118 for operative contact with the control arm 117 for activating the said limit switch on relative rearward movement .of the larm assembly and associated follower mechanism.

Operational Sequence of Arm Automatic The Linarc (Line-Arc) Extractor Arm, as shown in FIG. 1, is in a normal waiting position. The arm operating `double `acting air cylinder 81 is connected to a solenoid operated valve section 119. Cylinder port 120 is pressurized while port 121 is open to exhaust. Power Roller Automation Jaw 69 is attached in its hanger 65, the hanger being adjustably attached lto mount arm assembly 59-63. The double acting air cylinder 67 of the jaw is connected to a solenoid operated, 4-way valve, 122. Port 12.3 is pressurized, and port 124 is open to exhaust. This maintains the jaw in a retracted waiting position to the left of the position `shown in FIG. 1.

When the machine is energized through the control valves 122, port 123 in FlG. 1 is connected to exhaust and port`124 is pressurized. The jaw arm assembly moves forward to the position shown in FIG. 1, and the jaw 73 closes gripping the part but .after the rod 71 has moved the full length so Ithat the stop 72 engages the housing 66. Thereafter the solenoid control valve assembly 119 is activated supplying air pressure to the port 121 of the cylinder 81, connecting port 120 to exhaust.

The piston rod 79 of cylinder 81 starts to retract with the clevis 78 carrying the follower assembly rollers 84 and 86 alo-ng with telescoping arm SS and the relative attached assemblies. Swing plate assembly 30, with support plate assembly 49 starts to swing at the same time the telescoping arm begins to shorten, creating lift. This swing and lift combination controls the jaw pickup point to now inscribe a straight line 99 inclined relative to the horizontal and iinally depending upon the slot relationship of side plates 12 to the swing plate assembly 30, as the acti-on continues the swing, the telescopingrarm reverses direction.

The purpose of the reverse was to impart a reverse Vinertia on the part held in the jaw. As the end ofthe follower shait 118 contacts roller arm 117 of the limit switch 116, the valve 122 is energized, or activated, .so -as -to reverse the air flow to the respective opposite ends of the cylinder 67 .applying pressure tluid to port 123, causing the arm 64 to drop the part beingremoved v`from the press.

The a-bove described adjustability of the press mount 19 relative to pivot 26 and the arcuate control slots 28 thus establish a predetermined angularity of the complete assembly suspended from the press mount and secured thereto. The purpo e of varying this angul-arity is vfor regulating the contour of the paths of withdrawing `movement of the work from rthe press, such as to one of the intermediate path indicated in dotted lines at 126 and 127.

Likewise the above adjustability factor of the swing plate assembly 30 relative to the support assembly 49 by the interchange o f fasteners 50, also makes provision for a regulation of the control paths of withdrawing movement of the work engaging member 64.

The bottom path, designated at 123 `indicates the type of path which may be achieved in the prior art, namely a constant radius. It has been described above that one of the primary objects of invention is to avoid a constant radius in the withdrawing movement and to achieve initially a lift, as indicated, the other control paths shown followed by a straight line rectilinear movement and terminating in an arcuate movement which is achieved by the construction and operation of the above fully described.

As above described, the angular relation between slots 87 in plates 12 and slots 85 in plates 31 determine the pivotal movement of the swing plate assembly 30. Variation in this angularity will effect the final compound movement of clamp arm 64, taking into consideration the initial retracting movement of the telescoping arm assem- -bly 55.

' lt is contemplated also that the shape of the slots 85 and 37 may be varied for the production or differential movements of theV swing plate assembly and associated jaw assembly. For example, the slots and 87, and particularly the slots 85 may be arcuate or semi-circular.

Conclusion From the foregoing, it will readily be seen that the work extractor arm herein disclosed essentially comprises a body l2, means at its upper end for supporting it upon the press; a swing 31 pivotally mounted at 33 at the upper end of the swing on the body and depending therefrom; an arm 55 slidably mounted at its upper end on said swing and depending therefrom to move an elongated work engaging jaw assembly adjustably mounted at the lower end of the arm and extending horizontally for reciprocal projection into the press. The arm 55 moves upwardly and downwardly. The arm 55 is mounted in a tube 52 in turn mounted in a pair of support plates 49 adjustably secured to the swing 31 and in essence support 49 forms a part of the swing 31.

The device further includes a motor 81 mounted on the body which includes an upwardly and downwardly reciprocating rod 79 pivotally connected at its lower free end to the upper end of the arm and to the swing. The means for establishing such pivotal connection includes the cross pin S0. The latter has four rollers on it for guiding the swing 31 and the arm 55 as they are moved upwardly by the motor acting through its rod 79. These rollers ride in a vertical slot 85 in the swing 31 and also ride in a nearly vertical slot 87 of the body 12.

, v7 Slot 87' in the body is at an acute angle to the slot 85 of the swing. The swing rotates 90 clockwise as shown in FIG. 3 so that the slot 8S moves from the vertical lower position to the horizontal upper position and the' ycross pin 8) moves in the path determined by slot S7 vreference should be had to the claims which follow.

I claim:

.1. In a work extractor arm for a press; a body; means at its upper end for supporting it upon said press; a swing pivotally mounted at its upper end on said -body and depending therefrom; an arm slidably mounted at its upper end on said swing and depending therefrom to -move upwardly and downwardly; an elongated work engaging jaw assembly adjustably mounted at the lower free end of said arm and extending horizontally for reciprocal projection into said press; a motor mounted on the body including an upwardly and downwardly reciprocating rod pivotally connected at its lower free end to -the upper end of said arm and to said swing; and means for guiding the swing and the arm as they are moved upwardly by the motor; said means comprising a cross 'pin connected to the upper end of the arm riding in a vertical slot in the swing and also riding in a nearly vertical slot of the body, at an acute angle to the s'lot of the swing; whereby upward movement of the reciproeating rod of the motor lifts the jaw assembly and rearwardly swings said swing on said body to produce in said jaw assembly successively rectilinear and rotary movements.

2. In the work extractor arm of claim 1, said swing including spaced plates and an elongated tube between and xedly secured to said plates; said arm being slidably mounted within said tube.

3. In the work extractor arm of claim 2, a mount arm for said jaw assembly slidably positioned within and adjustably secured to said tube.

4. In the work extractor arm of claim 1, each of the body and the swing comprising parallel spaced plates, with the connection between said reciprocating means and said arm including said cross pin; there being a first pair of opposed elongated slots formed through said swing plates, and a pair of opposed elongated slots formed through said body plates, extending at an acute angle to the slots of the swing plates; said cross pin being movably positioned within said swing plate slots and within said body plate slots.

References Cited in the file of this patent UNITED STATES PATENTS Re.18,133v Westin July 21, 1931 1,959,512 Wall May 22, 1934 2,609,776 Sahlin Sept. 9, 1952 2,677,342, Miller May 4, 1954 2,868,582 Loisell Jan. 13, 1959 2,948,417 Haanes Aug. 9, 1960 3,040,685 Ridley June 26, 1962 

1. IN A WORK EXTRACTOR ARM FOR A PRESS; A BODY; MEANS AT ITS UPPER END FOR SUPPORTING IT UPON SAID PRESS; A SWING PIVOTALLY MOUNTED AT ITS UPPER END ON SAID BODY AND DEPENDING THEREFROM; AN ARM SLIDABLY MOUNTED AT ITS UPPER END ON SAID SWING AND DEPENDING THEREFROM TO MOVE UPWARDLY AND DOWNWARDLY; AN ELONGATED WORK ENGAGING JAW ASSEMBLY ADJUSTABLY MOUNTED AT THE LOWER FREE END OF SAID ARM AND EXTENDING HORIZONTALLY FOR RECIPROCAL PROJECTION INTO SAID PRESS; A MOTOR MOUNTED ON THE BODY INCLUDING AN UPWARDLY AND DOWNWARDLY RECIPROCATING ROD PIVOTALLY CONNECTED AT ITS LOWER FREE END TO THE UPPER END OF SAID ARM AND TO SAID SWING; AND MEANS FOR GUIDING THE SWING AND THE ARM AS THEY ARE MOVED UPWARDLY BY THE MOTOR; SAID MEANS COMPRISING A CROSS PIN CONNECTED TO THE UPPER END OF THE ARM RIDING IN A VERTICAL SLOT IN THE SWING AND ALSO RIDING IN A NEARLY VERTICAL SLOT OF THE BODY, AT AN ACUTE ANGLE TO THE SLOT OF THE SWING; WHEREBY UPWARD MOVEMENT OF THE RECIPROCATING ROD OF THE MOTOR LIFTS THE JAW ASSEMBLY AND REARWARDLY SWINGS SAID SWIG ON SAID BODY TO PRODUCE IN SAID JAW ASSEMBLY SUCCESSIVELY RECTILINEAR AND ROTARY MOVEMENTS. 